diff --git a/common.sh b/common.sh
index 7aeddc3598..aad6e75c25 100644
--- a/common.sh
+++ b/common.sh
@@ -660,47 +660,6 @@ get_git_id() {
   git var GIT_COMMITTER_IDENT | sed -e 's/^.*<\(\S\+\)>.*$/\1/'
 }
 
-# These two helpers clobber the ro compat value in our root filesystem.
-#
-# When the system is built with --enable_rootfs_verification, bit-precise
-# integrity checking is performed.  That precision poses a usability issue on
-# systems that automount partitions with recognizable filesystems, such as
-# ext2/3/4.  When the filesystem is mounted 'rw', ext2 metadata will be
-# automatically updated even if no other writes are performed to the
-# filesystem.  In addition, ext2+ does not support a "read-only" flag for a
-# given filesystem.  That said, forward and backward compatibility of
-# filesystem features are supported by tracking if a new feature breaks r/w or
-# just write compatibility.  We abuse the read-only compatibility flag[1] in
-# the filesystem header by setting the high order byte (le) to FF.  This tells
-# the kernel that features R24-R31 are all enabled.  Since those features are
-# undefined on all ext-based filesystem, all standard kernels will refuse to
-# mount the filesystem as read-write -- only read-only[2].
-#
-# [1] 32-bit flag we are modifying:
-#  http://git.chromium.org/cgi-bin/gitweb.cgi?p=kernel.git;a=blob;f=include/linux/ext2_fs.h#l417
-# [2] Mount behavior is enforced here:
-#  http://git.chromium.org/cgi-bin/gitweb.cgi?p=kernel.git;a=blob;f=fs/ext2/super.c#l857
-#
-# N.B., if the high order feature bits are used in the future, we will need to
-#       revisit this technique.
-disable_rw_mount() {
-  local rootfs=$1
-  local offset="${2-0}"  # in bytes
-  local ro_compat_offset=$((0x464 + 3))  # Set 'highest' byte
-  printf '\377' |
-    sudo dd of="${rootfs}" seek=$((offset + ro_compat_offset)) \
-            conv=notrunc count=1 bs=1
-}
-
-enable_rw_mount() {
-  local rootfs=$1
-  local offset="${2-0}"
-  local ro_compat_offset=$((0x464 + 3))  # Set 'highest' byte
-  printf '\000' |
-    sudo dd of="${rootfs}" seek=$((offset + ro_compat_offset)) \
-            conv=notrunc count=1 bs=1
-}
-
 # Generate a DIGESTS file, as normally used by Gentoo.
 # This is an alternative to shash which doesn't know how to report errors.
 # Usage: make_digests -d file.DIGESTS file1 [file2...]